HOME JOURNALS CONTACT

Journal of Biological Sciences

Year: 2011 | Volume: 11 | Issue: 6 | Page No.: 423-427
DOI: 10.3923/jbs.2011.423.427
Development of Bivoltine Pure Strains of Silkworm, Bombyx mori L. to Rear Eexclusively on Artificial Diet During Young Instar
J.S. Nair, S.N. Kumar and K.S. Nair

Abstract: As component bivoltine pure strains of existing productive silkworm hybrids did not accept the artificial diet, the study was taken up to create a pool of such strains which would feed on the artificial diet. Six strains viz., 5HT, GEN4, 8HT, B71, CSR3 and JPN8 were short-listed based on the results of an initial screening which recorded feeding response percentage of more than 20. These six strains were further subjected to continuous inbreeding and directional selection for 12 generations for improving the feeding response over the generations and stabilizing it at more than 85% so that they would form suitable breeding resource materials for preparation of commercial bivoltine hybrids for exclusively rearing on artificial diet during young instar. Care was taken so that breed characters in terms of economic traits were not adversely affected. At the end of ninth generation, the feeding response reached above 78% except in B71 and further stabilized at the higher level and thus forming prospective parents for bivoltine hybrid combinations. Data pertaining to G9~G12 were analyzed to check the stability in performance. The traits with particular reference to the diet phase such as feeding response, young instar larval duration and young instar larval weight have reflected non-significant differences in the last four generations clearly indicating the stability in these traits. Other traits such as cocoon weight, cocoon shell weight, shell percentage, survival and cocoon yield also did not vary among the generations. After the strains were stabilized for rearing on artificial diet, they were designated as 5HT (A), GEN4 (A), 8HT (A), B71 (A), CSR3 (A) and JPN8 (A) as these strains are different from the normal strains (5HT, GEN4, 8HT, B71, CSR3 and JPN8). The implications of the improved feeding response and stabilized economic traits in the context of this study are discussed.

Fulltext PDF Fulltext HTML

How to cite this article
J.S. Nair, S.N. Kumar and K.S. Nair, 2011. Development of Bivoltine Pure Strains of Silkworm, Bombyx mori L. to Rear Eexclusively on Artificial Diet During Young Instar. Journal of Biological Sciences, 11: 423-427.

© Science Alert. All Rights Reserved